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How do I animate opacity change inside a waypoint function based on scroll position?

I am working on a project, here: https://github.com/erinreiss/spaceship1/tree/ministory1
And I am looking to make a div#landing to go from opacity:1 to opacity:0 within 200 pixels of scrolling, based on scroll position. I was able to do it successfully like this:
var target = $('#landing');
var targetHeight = 200;
$(document).scroll(function(e){
var scrollPercent = (targetHeight - window.scrollY) / targetHeight;
if(scrollPercent >= 0){
target.css('opacity', scrollPercent);
}
});
Now, I want to use waypoints to trigger this same effect but at a different time. I want instead of it firing as the div#landing moves out of the viewport, it instead fires as a defined Waypoint (in this case, a different div#intro1) is scrolled past.
This is my attempt:
var target = $('#landing');
var targetHeight = 200;
var intro1 = $('#intro1').waypoint(function (direction) {
console.log('bam!');
$(document).scroll(function(e){
var scrollPercent = (targetHeight - window.scrollY) / targetHeight;
if(scrollPercent >= 0){
target.css('opacity', scrollPercent);
}
})
}, {offset: 200});
The waypoint fires, but (alas) the scrolling opacity changer does not work...
Any advice? Thank you!!
ps - The other thread with this question is answered with code no longer available :(
How do I animate on scroll inside a waypoint function?

I didn't solve this problem, but I did hack something together close to what I wanted... It allows me to use the scroll position of an overflow element to trigger and define the level of opacity on another element.
See solution here:
https://github.com/erinreiss/spaceship1/tree/ministory1
var target = $('#intro1inner');
$('#intro1inner').scroll(function(){
//define a variable that will be how much the target has scrolled from its original position
var changeA = target.scrollTop()
console.log('changeA:' + changeA)
// I want my change in opacity (from 0-1 to take place over 250px)
var scrollPercent = changeA / 250;
console.log('scrollPercent:' + scrollPercent)
});

How to get divs to be the same width in jQuery?

I'm using this JQuery to get a div to be the same width as another when the window width is less than 1200px and can't figure out what mistake I'm making.
var width = $('.creative').outerWidth();
if ($(window).width() < 1200){
$('#right-child').css('width', width);
}else{
console.log('more than 1200');
};

Try to concatenate the value with unit name.
$('#right-child').css('width', width + 'px');

Guess I know whats the problem, your code is right! but... If you test these code with the width of the browser in full, nothing will change. You need to add .resize event (https://api.jquery.com/resize/), just that!
$(window).resize(function(){
console.log('resize!');
var width = $('.creative').outerWidth();
if ($(window).width() < 1200){
$('#right-child').css('width', width);
}else{
console.log('more than 1200');
};
});
If the problem persist, just let me know.

Jquery - Animate by scroll positions to work the same on window resize

Hey I have this really annoying issue thats probably got a simple solution but for the life of me i cant find away to fix it.
Basically i have two images both 50% with of it's container now the goal is the both images to slide in (left/right) on the basis of the scroll position and once it get to the top of the container both images will sit is place.
Now i got that working to that point the only issue is when i resize the page the position of both images are wrong. I obviously did a resize() function with the same logic as the scroll() function but still i got nowhere. Here's my code
var page_width = $(document).outerWidth(),
page_height = $(document).outerHeight(),
left_image = $('.split-screen.youth'),
right_image = $('.split-screen.elite'),
offset = (page_width) / page_height;
left_image.css({'left':'0px'});
right_image.css({'right':'0px'});
$(window).on('scroll', null, function(){
var scrollTop = $(window).scrollTop(),
calc = -(scrollTop*offset);
left_image.css({
'margin-left': 'calc(100% + '+calc+'px)'
});
right_image.css({
'margin-right': 'calc(100% + '+calc+'px)'
});
});
$(window).resize(function(){
// something ???
});
Here is a jsFiddle of the issue although it doesn't look entirely accurate but you get the picture. When you resize the scroll position changes and i need the margin-left/margin-right values to be correct.

I think your problem is that you're still using the old offset value. Just update your global values first, than it works for me (see: https://jsfiddle.net/a7tfmp37/2/):
$(window).resize(function(){
page_width = $(document).outerWidth(),
page_height = $(document).outerHeight(),
offset = (page_width) / page_height;
var scrollTop = $(window).scrollTop(),
calc = -(scrollTop*offset);
left_image.css({
'margin-left': 'calc(100% + '+calc+'px)'
});
right_image.css({
'margin-right': 'calc(100% + '+calc+'px)'
});
});

Get browser width and height after user resizes the window

Is there any way to get the browser width and height after a user has resized the window. For example if the window is 1920 by 1080 and the user changes the window to 500 by 500 is there any way to get those two new values in JavaScript or jquery?

Pure Javascript answer:
var onresize = function() {
//your code here
//this is just an example
width = document.body.clientWidth;
height = document.body.clientHeight;
}
window.addEventListener("resize", onresize);
This works fine on chrome. However, it works only on chrome. A slightly more cross-browser example is using the event target properties "outerWidth" and "outerHeight", since in this case the event "target" is the window itself. The code would be like this
var onresize = function(e) {
//note i need to pass the event as an argument to the function
width = e.target.outerWidth;
height = e.target.outerHeight;
}
window.addEventListener("resize", onresize);
This works fine in firefox and chrome
Hope it helps :)
Edit: Tested in ie9 and this worked too :)

If you need to know these values to do layout adjustments, I bet you plan on listening to those values. I recommended using the Window.matchmedia() API for that purpose instead.
It is much more performant and is basically the JS equivalent of CSS media queries.
Very quick example of use:
if (window.matchMedia("(max-width: 500px)").matches) {
/* the viewport is less than or exactly 500 pixels wide */
} else {
/* the viewport is more than 500 pixels wide */
}
You can also setup a listener that'll get called every time the state of the matches property changes.
See MDN for description and example of using a listener.

It's possible by listening to resize event.
$(window).resize(function() {
var width = $(window).width();
var height = $(window).height();
})

You can use the JQuery resize() function. Also make sure you add the same resize logic to reload event. If user reloads in the sized window your logic won't work.
$(window).resize(function() {
$windowWidth = $(window).width();
$windowHeight = $(window).height();
});
$(document).ready(function() {
//same logic that you use in the resize...
});

Practically, I use this and it helps me a lot:
var TO = false;
var resizeEvent = 'onorientationchange' in window ? 'orientationchange' : 'resize';
$(window).bind(resizeEvent, function() {
TO && clearTimeout(TO);
TO = setTimeout(resizeBody, 200);
});
function resizeBody(){
var height = window.innerHeight || $(window).height();
var width = window.innerWidth || $(window).width();
alert(height);
alert(width);
}

You can use the resize event, along with the height() and width() properties
$(window).resize(function(){
var height = $(window).height();
var width = $(window).width();
});
See some more examples here

Use jQuery resize method to listen window size change . inside callback you can get height and width.
$(window).resize(function(){
var width = $(window).width();
var height = $(window).height();
});

Simplest way to get real width and height of an element after window resize as the follow:
<div id="myContainer">
<!--Some Tages ... -->
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script>
$(function () {
$(window).resize(function () {
//The below two lines of codes more Important to clear the previous settings to get the current measure of width and height
$('#myContainer').css('height', 'unset');
$('#myContainer').css('width', 'unset');
var element = $('#myContainer');
var height = element.height();
var width = element.width();
//Below two lines will includes padding but not border
var innerHeight = element.innerHeight();
var innerWidth = element.innerWidth();
//Below two lines will includes padding, border but no margin
var outerHeight = element.outerHeight();
var outerWidth = element.outerWidth();
//Below two lines will includes padding, border and margin
var outerHeight = element.outerHeight(true);
var outerWidth = element.outerWidth(true);
});
});
</script>

You can use the event object to get the height and width, I use destructuring assignment and the target points to window:
const handleGetDim = ({ target }) => ({
width: target.innerWidth,
height: target.innerHeight,
});
window.addEventListener('resize', handleGetDim);

Resizing images in Chrome using JQuery

I just ran into the weirdest of bugs today. I'm not sure if it's a bug in Chrome or something that I can work around but here goes.
I built a JQuery function to resize a set of images that are posted on a forum:
$(".post-message img.post-image").load(function(){
$(this).each(function() {
var maxWidth = 200;
if($(this).width() > maxWidth)
{
var factor = $(this).width() / maxWidth;
var width = $(this).width();
var height = $(this).height();
$(this).css('width', width / factor);
$(this).css('height', height / factor);
}
});
});
The problem is that this only seems to work when I refresh the page. It doesn't work when you press previous or when you get linked to the page.
In chrome the $(img).width() property returns 0 in both cases when the function doesn't work.
This function performs as expected in IE9 and FF3
What can I do to fix this odd behavior?

Most probably because the images are being pulled up from the browser cache, and the load event is not triggering. The way around this is to manually trigger load if the images's complete properties have been set:
$(".post-message img.post-image").one("load", function(){
$(this).each(function() {
var maxWidth = 200;
if($(this).width() > maxWidth)
{
var factor = $(this).width() / maxWidth;
var width = $(this).width();
var height = $(this).height();
$(this).css('width', width / factor);
$(this).css('height', height / factor);
}
});
}).each(function() {
if(this.complete) $(this).trigger("load");
});

Karmin is correct here. I ran into this problem a few years ago and ended up just not relying on img.load. His workaround for manually triggering the load event should work.
However...
Developers should do max-width or height in CSS in this scenario. In fact, it is good programming practice to do what one can in CSS before doing them in javascript.
Additionally, if one were to keep going with this solution, var width and var height should be placed outside of the if statement next to var maxWidth, and used wherever $(this).width() is called (including the initial check on line 4). Right now the code is unnecessarily creating a new jQuery object to get the height each time when it should have stored and used the value from the first check.

Thanks for the contributions guys. A previous answer given on stack - that I apparently couldn't find this afternoon jQuery && Google Chrome - solved my problem!
$(window).load(function() {
$(".post-message img.post-image").one("load", function(){
$(this).each(function() {
var maxWidth = 200;
if($(this).width() > maxWidth)
{
var factor = $(this).width() / maxWidth;
var width = $(this).width();
var height = $(this).height();
$(this).css('width', width / factor);
$(this).css('height', height / factor);
}
console.log($(this).width())
});
}).each(function() {
if(this.complete) $(this).trigger("load");
});
});
The code has to be executed on $(window).load() together with the provided code by karim79.